In a posting on Twitter, Osbourne addressed "my darling" fellow judge Howard Stern and said, "money is not the reason I'm not returning" to the show. Her tweet trailed off with "it's because ...." and didn't elaborate.

Her message was unexpected, NBC Entertainment Chairman Robert Greenblatt told a meeting Tuesday of the Television Critics Association.

"This is coming out of context and sort of spontaneously, and we don't even know what's going on. And it's probably much ado about nothing," Greenblatt said, declining to comment further.

Osbourne has a multi-year contract with the series, said a person familiar with the production. The person, who lacked authority to discuss the issue publicly, spoke on condition of anonymity.

"America's Got Talent," which is now airing its seventh season, added Stern to the judges' panel this year and moved the production from Los Angeles to New York to accommodate him. Howie Mandel is the show's third judge.

Osbourne's representative did not immediately respond to a request for comment.

The tweet from Osbourne, co-host of "The Talk" and wife of rocker Ozzy Osbourne, appeared to refer to one posted Monday on the account for shock jock Stern's radio show.

Stern "isn't sure if he'll do another season and says Sharon Osbourne may not come back unless she gets more money," the tweet read.

Asked whether Stern intended to stay with the show, Don Buchwald, his agent, responded by email that "we do not respond to inquiries of this sort."

Earlier Tuesday, Paul Telegdy, NBC entertainment president of alternative programming, told the critics' meeting that he was "thrilled" with Stern.